My dad used to work on his cars. I like to think I helped, but I just held the light where he was working.

As cars get more and more complex, doing your own work is getting harder. We are all familiar with the dreaded “check engine” light. Most people take their cars to their dealers or a local mechanic to get them to read the engine codes and tell them what has gone wrong.

Almost every car made after 1996 has a port under the dashboard to connect diagnostic systems. This port is called the OBD-II port (on-board diagnostics).

It used to be that only dealers and mechanics had access to the computers and cables that could connect to the port, but technology advances have brought products that let people read their own engine codes.

I’ve been testing the ODBLink MX+ ($99.99) from, which uses a wireless dongle to connect your car to your smartphone, tablet or Windows PC via Bluetooth. Your car can yield a wealth of information if you know how to get to it.

If your car is like mine, it has a small display on the dash that shows things like miles per gallon in real time, your engine’s revolutions per minute and the car’s speed in miles per hour. Depending on your car, it may display more or less information.

My Honda Fit has a simple light for engine coolant temperature (blue for too cold, red for too hot). These types of lights are commonly called “idiot lights.” Cars used to have actual gauges that showed the temperature, but now we get idiot lights. My car knows the exact temperature of the coolant, but I can only see it if I have access to the OBD-II port.

There are all kinds of engine statistics you can access if you have a device like the OBDLink MX+.

The ODBLink MX+ has apps for iOS, Android and Windows (sorry, Mac users) that can display all the information that can be extracted from your car. The app lets the user completely customize information screens called dashboards that consist of digital or analog gauges that can be set up in different sizes and shapes. You can have multiple dashboards for different situations.

You can set up one for fuel mileage information, one for engine performance, one for speed and acceleration rates and so on.

One very cool feature of the ODBLink app is that you can put the dashboards into “heads up display” mode, which flips the screen so you can place your phone on your dashboard to see the display reflected on your windshield as you drive. It’s a slick feature.

If you have your own favorite car app that uses ODB-II data, chances are the ODBLink MX+ will work with it. The app stores for iOS and Android are filled with different apps to access the data. There is a list of compatible apps on

The ODBLink MX+ can read engine error codes to let you know exactly why your check engine light is on. The included app has information on thousands of codes, so you are presented with a clear explanation of what’s happening. Cheaper OBD-II dongles just give a code number and make you look up the error.

The MX+ can also clear the dash lights if you like. Of course, those lights are on for a reason, and unless you know the severity of the problem, you should not just turn off the lights without checking with a mechanic.

The MX+ takes a bit of time to set up the first time you use it.

You’ll download the app and then plug the dongle into your car’s ODB-II port. If you’re not sure where your port is, just Google the specific year and model and the words “ODB-II port location” and you’ll find it.

Every car I’ve tried has it located on the driver’s side, under the dash to the left or right of the steering column. You’ll likely have to get your head down near the floorboard to see where it is.

When it’s connected, you’ll see a power light and a Bluetooth light come on. You’ll need to go to your phone’s Bluetooth preferences and look for the dongle to appear in the list of available connections. Make the connection and then launch the app and you’ll see the main screen, where you’ll still need to touch the “connect” button.

I never had trouble getting it connected, but I did need to press the connect button each time until I found the setting for having it connect automatically.

I’d like to say I customized the heck out of the dashboards, but in reality, I used the default gauges and they all worked really well. The MX+ has no trouble communicating the car’s information the app.

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